Know Thy Partner
by Memnorak
Summary: Beckett may not know her shadow quite as well as she thought.


A/N: I own nothing; all characters, etc. belong to ABC/Beacon/Experimental or Mutant Enemy/Fox. My first fic, published or otherwise. Set some time after Last Call for Castle, vague references to Serenity (the episode) and Safe for Firefly. I don't have a particular moment in time in mind, so please excuse any inconsistency with canon Castle/Gina and Beckett/Josh relationships, I'm just kind of ignoring them.

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><p>She knew she shouldn't have come. <p>

She has read all of his books, most more than once. She had gotten inside his head, used his imagination as a substitute for her own at a time when all her mind could provide was nightmares. And after working with Rick Castle in person for over two years, Detective Kate Beckett likes to think she knows what makes him tick.

But knowing that it is coming does nothing to quell the sudden surge of annoyance at herself that she feels as she opens the door to the Old Haunt and steps through, only to look towards the bar and lock onto the amused gaze and self-satisfied smirk of the man standing behind the counter.

She just had to go and prove him right. Now, he'll be insufferable... -er. Insufferabler. Almost certainly not a word, but it might be useful later just to watch him cringe. Even the murdering of the English language, unfortunately, would not likely distract him from his gloating for long. And if he realized she was deflecting (which he would; annoying as he may be, she can't honestly say he's a half-bad investigator when it comes to reading people), that damn smirk would only mimic his ego and grow to ever-increasing proportions.

She _knew_ she shouldn't have come.

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><p>The case had been a long and frustrating one, made all the more irritating by the fact that it had been solved so early on. The murderer was the son of a wealthy retired (and now deceased) investment banker, and who had decided that his trust fund just wasn't enough to justify waiting another decade or two for his full inheritance. It was as cut-and-dry as they come, and Beckett and her team had easily put the pieces together in the first twelve hours of the case. A lack of hard evidence, however, had led to almost a week of fruitless searching. Finally, a crazy intuitive leap by Castle ("Why would a multi-millionaire care so much about getting -that- tuxedo released from evidence?") had led them to the murder weapon (bow-ties: fashion accessory and prime strangulation tool), which let them finally make the arrest.<p>

That afternoon, Castle had approached her at her desk.

"No."

"C'mon Beckett, surely the paperwork can wait until tomorrow."

"Castle, go home. Spend some time with Alexis. I have work to do. Besides, it's a Tuesday."

"All the more reason to come, my dear Detective. Long case, dealing with a bunch of two-thousand-an-hour lawyers, five cups of coffee since we got back to the station..."

"Wait, you've been counting? That's just creepy, Castle."

"My point still stands. You're too wound up. If you just go home, you'll either end up watching reruns on TV or lying awake in bed, and you'll be exhausted tomorrow. Come down, get a drink, relax for an hour or two. I'm not suggesting we go out and get drunk. Unless you're offering, in which case..."

"Goodnight, Castle."

And that was that. Or so she thought, until she ended up back at her apartment, bored out of her mind and too awake to try to make an early night of it. As she sat on the couch, staring blankly at reruns on her TV, a little voice in the back of her head, which sounded suspiciously like a certain writer she knew, suggested that maybe, just maybe, one drink and a little company wouldn't hurt.

As she kept searching for ways to relax in her apartment, that annoying little voice kept getting louder and louder, until she finally decided to shut it up by grabbing her keys and heading out the door.

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><p>Which led her here, standing in the doorway watching him turn back to the gathered businessmen at the bar. He jumps back into the conversation in true Castle fashion; even from a distance, she can see that the customers are completely under his spell, no doubt hanging on every over-exaggerated word of whatever tale he is telling. She can't help but smile, shaking her head in sympathy for the group. In a few hours, when they finally break free from debating the plausibility of whatever story Castle is currently embellishing long enough to check their watches, they'll realize that they've stayed out far later than they originally planned. At least Castle only seems to use his well-practiced skills of distraction on the wealthier clientele. A civilized way of fleecing the rich to give to the... well, presumably himself; she knows that if he could read that thought, he'd tease her mercilessly about her just wanting to see him in Robin Hood tights.<p>

Which she didn't. At all. Hah, in his dreams. 'Great, now I'm defending myself against even imaginary Castle comments. I've been spending way too much time with him.'

Just the sight of him, across the room, seems to be all it takes to make that Castle-voice in her head come back at full volume.

She knew she shouldn't have come. 

Brought back out of her thoughts by a near miss with a waitress and a precariously balanced tray of drinks, Beckett switches off auto-pilot and starts to take in her surroundings. The Old Haunt is not terribly crowded, which is not surprising given the fact that it's a Tuesday night, but there are enough people around to grant a kind of comfortable, cozy atmosphere. She surveys the gathered crowd, pleasantly surprised to see that there is a wide range of patrons present. After getting stonewalled by countless rich lawyers in thousand-dollar suits for a week, she had not been looking forward to trying to unwind in a bar full of the same. It seems, however, that despite the pub's history of attracting (and now being owned by) famous writers and the like, tonight it has pulled in everyone from the businessmen up by Castle to a few grease-covered mechanics, just off their shift and unwinding in the corner.

In one case, the two ends of the class spectrum seem to have strangely mixed, Beckett notes as she passes by a pair of men seated in a dimly lit booth off to the side of the main bar. A young man in a hooded sweatshirt and jeans, glancing around nervously as he speaks in low tones to a man in an ill-fitted suit jacket with a bowler hat pulled low over his face. The detective in her, which (un)fortunately never seems to switch off, tells her to take a closer look. A drug deal? No, in that case Hoodie would be a little smoother, and his client would be the nervous one. Besides, Castle didn't have the lights dimmed -that- low; the deal would be in plain sight. Even a nervous first-time dealer would be smarter than that. Might be worth keeping an eye on them, but the chances of anything criminal happening in Castle's bar were slim to none. Besides, wasn't the whole point of this little outing to relax?

Not that she needed to come here to relax, she reminds herself as she takes a seat at the bar and is greeted with the up-close-and-personal version of Castle's smug little grin. She could have relaxed at home, eventually. She just changed her mind and decided, independently of Castle's predictions, that she could use a drink. Right.

She has the good sense not to even bother trying to make that argument out loud.

"Beckett, what a surprise! I didn't think you'd make it." His smile tells her that he knew full well she would, but she can't help but notice that underneath the amusement he is genuinely pleased that she is there. And when Castle is genuinely pleased, he tends to take it out on everyone around him. Maybe this wasn't the best idea, after all.

"I was going to stay in, but I figured I would do the charitable thing and save some poor woman from listening to the twentieth retelling of how you 'single-handedly' discovered the Mayor's stash." Not the best she's ever come up with, but it helps to keep the conversation on-track, and away from dangerous territory. Like how he only seems to be getting better at making her "change her mind independently" lately.

"Why Detective Beckett, are you really that worried that I might take all the credit? Or are you just jealous at the thought of me applying my considerable charms towards someone besides you?"

She rolls her eyes at him, and turns to glance around the bar, immediately suppressing her grin. Over the course of their pseudo-partnership, they had developed an intricately choreographed dance. An observation, a quick barb, a suggestive comment, a dismissal. Each move carefully met and countered, stepping close enough to keep things interesting but never quite meeting. They'd been at it for long enough that even their body language had become part of the game. No matter how quickly she hid it, he caught her hint of a smile every time. And whether he knew it or not, she always picked up on the way his chest puffed out slightly with pride over drawing a reaction from the unflappable Detective Beckett.

Almost against her will, her eyes are drawn to the two odd men from before, now mostly hidden from view. Hoodie suddenly stands up, as if to leave, but a low, terse "Sit. Down." from his associate quickly puts him back in his place, figuratively and literally. Interesting; Suit Jacket is running the show, it seems.

No. Not interesting. Two people quietly arguing in a bar are not interesting. At least not now. Off duty means no duties. Starting now.

Bolstered by her newfound resolve (and, of course, not at all by the fact that she has seen no evidence even hinting at illegal activity besides choosing a dark booth), Beckett turns back towards the bar just in time to catch the last couple words of whatever Castle was just saying. Crap. Of course he was talking to her. When is he _not_ talking? 'He'll live,' she thinks as she takes a sip of the drink that had magically appeared while she was distracted. This is hardly the first time she's ignored him, although she usually has to consciously tune him out. Maybe he's right ('again', says the little voice, which she quiets with another sip), she does need to unwind after being "Detective Beckett" for far too many hours running.

She suddenly realizes he's still waiting for an answer. "I've gotta say, Castle, if your idea of 'relaxing' involves talking my ear off, I don't see why you couldn't just do that while I got my paperwork done."

He affects his usual cute... pathetic!... pathetic wounded puppy look, but it fades into a mildly confused expression. Damn, he must have noticed her hesitation. And knowing Castle like she does, she knows he's already forming a hundred questions to figure out why she spaced out.

Unwilling to admit that she's having trouble shutting off, and looking for anything to think about besides that slightly depressing fact, she decides a distraction is in order for both of them.

"So," Beckett prompts, pointing subtly towards a man sitting by himself at a table across the room, "what do you think his story is?"

A quick, understanding smile tells her he knows what she's doing, but he seems more than willing to oblige, letting her sudden reversal pass by unremarked and launching into some outrageous tale. It would worry her more, the additional reminder of just how well they know each other, if it weren't for moments like these when she's too grateful to care.

She lets herself get swept up in the story, letting herself chuckle as the cast of characters grows to encompass half the patrons in the bar, and somehow morphs from murder to espionage to space pirates. Alexis must have been truly lucky, to have grown up with this man around to spin a new and exciting bedtime tale every night. Sure, Beckett had grown up perfectly happy listening to the same few tried-and-true favorites from her parents, but having her own personalized fairy tales would have felt that much more special as a little kid. It was nice now and then as an adult, too.

The silence from across from her finally registers, as she realizes he's gone perfectly still. It's odd; in all the time she's known him, Richard Castle has very rarely been able to contain all that enthusiasm and energy and actually sit still, much less stop while he's on a roll. She follows his eyes over to the table that had bothered her before, the one been forcing herself to ignore until Castle had kindly distracted her. Two brothers, looking to buy cattle from the space pirates, if she remembers the ridiculous plot correctly. Unfortunately, she grudgingly admits, it makes about as much sense as anything she was able to figure out before. She starts listening again, hoping to figure out what has him so unsettled.

"... A man like yourself, you may not pay any mind to a skirmish with the boys in blue, but I'm a businessman, see? Roots in the community. And I won't have my name caught up with yours in a mess with the law on account of your petty thieving. Got me a reputation to uphold."

Between making a note to pat down Hoodie for stolen goods and trying to place Suit Jacket's odd accent, she almost misses the slight motion from behind the bar. She turns, and her eyes widen as she sees Castle slowly sliding a gleaming revolver out from the bar and slipping it into a pocket, his disturbingly cold gaze never leaving the darkened booth.

"Castle! What are you doing? Where did you even get that thing?" she hisses, reaching for her own weapon and quickly turning to assess the room for threats.

"Beckett," he cuts in, reaching across the bar with his unoccupied hand to grab her arm (her weapon arm; clueless though he is, he should know better than that by now), "don't. Stay here."

"Castle, what the hell is going on?" She tries to shake her arm free, and is shocked to find that his grip, while not tight, is firm as iron. She turns back to glare at him, and is taken aback by the hardness she sees in his features, the calculating look he gives the whole room. The way he quickly scans for targets and exits reminds her of seasoned cops, veterans, the types of people Castle is most definitely not. She shakes it off, however, determined to take control of the situation.

"Castle, tell me what is happening right now, or so help me-"

"Kate," he cuts her off again, though with a slightly softer tone than before, "I need you to trust me, and let me handle this." As suddenly as it appeared, the warmth disappears. "Whatever happens, let it play out, _dong ma_?"

She can't even begin to process where the slight accent is coming from, or what that last comment in Chinese means, and she tries to reach out for him as he releases her arm. "Rick, ..."

"Detective." He turns his eyes briefly down from the booth to lock with hers, and she can't help the slight shiver of fear as she sees just how completely his usual goofiness has been replaced with barely restrained violence. "Let. It. Play."

This isn't right. Castle's not supposed to be threatening, he's supposed to be a playboy, a celebrity, a loving father, a dutiful son, her partner. A mix of roles and personalities that he somehow juggles on a day-to-day basis with ease. This Castle is unfamiliar, a total departure from everything she knows about him, and that scares her more than anything else.

He slips out from behind the bar, moving so quietly that she has to stifle a twinge of irritation that he could never shut up and behave like this when they were in the field. She feels the sudden, inappropriate urge to laugh at the absurdity of the situation, but the moment quickly passes as she focuses on the armed man moving to confront two criminals.

But he's not just an armed man, he's a friend. He is a friend, right? Or are they NYPD detective and shadow, author and muse, Nikki and Rook, a guy and a girl having a drink at a bar? A cop and the partner she knows and lo-... tolerates? They are so many things to each other; how had she never seen this part of him before? Maybe, just maybe, if she closes her eyes for a moment, she'll open them and find that this is all just a nightmare, that her world isn't coming apart at the seams.

She opens them again to watch Castle efficiently haul Hoodie up and out of his seat, tossing him towards the door and sitting down in his place. He faces Suit Jacket with a calm, cocky smile on his face and murder in his eyes.

"Seems to me I told you, once; wheel never stops turning, Badger."

Beckett is on her feet and reaching for her gun before her conscious mind processes the '_click_' of the hammer of Castle's gun being pulled back. She knows she's already wasted too much time; she's an officer of the law, and she has to act now, before something happens, before she has to try to explain to Alexis why her father is going to jail for homicide when she can't even begin to understand it herself.

And as she draws her weapon, Beckett feels a sudden chill to her bones, as she realizes that, in that moment, she doesn't know who to aim for. 

She has read all of his books, most more than once. She had gotten inside his head, used his imagination as a substitute for her own at a time when all her mind could provide was nightmares. And despite working with Rick Castle in person for over two years, Detective Kate Beckett really doesn't know the man at all.

She _knew_ she shouldn't have come.

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><p>AN: This idea's been rattling around in my mind for a while now, but I only recently decided to make myself get it down on paper. Please review, and I'd almost prefer criticism, I'd like to know where to improve. No plans to continue this at the moment; I'd love to figure out how Mal got to NYC and how Badger's involved, but even this much took an embarrassingly long time to get together.


End file.
